Once an order is created, click on the shipment (where the products are listed) to edit details of that shipment.
- Navigate to the Order and open it.
- Click anywhere on the shipment (where the products are listed).
- Under Shipping Details, click the ship method name (in green) and select the desired method.
- Click Save Changes
After saving changes, the shipping charge will be recalculated based upon the new method selected.